Wrestling is a sport practiced in various styles by two competitors, involving forcing an opponent to touch the ground with some part of the body other than his feet; forcing him into a certain position, usually supine (on his back); or holding him in that position for a minimum length of time. Wrestling is conducted in various styles with contestants upright or on the ground (or mat).

The three basic types of wrestling contest are the belt-and-jacket, catch-hold, and loose styles, all of which appear to have originated in antiquity. Belt-and-jacket styles of wrestling are those in which the clothing of the wrestlers provides the principal means of taking a grip on the opponent. In many cases this is no more than a special belt worn by both wrestlers, while in others a special belted jacket and special trousers are worn. Catch-hold styles require the contestants to take a prescribed hold before the contest begins; often this grip must be maintained throughout the struggle. Loose styles of wrestling, which are used in modern international competition, commence with the wrestlers separated and free to seize any grip that they choose except such as are explicitly forbidden (e.g., taking hold of an opponent’s clothing or using a life-threatening grip, such as a stranglehold).

Wrestling can also be classified in terms of what is required to win. These categories can be graded on an ascending scale of violence as follows: break-stance sports are those that require forcing the opponent to relinquish a certain posture or position; toppling requires that the standing opponent be forced to touch the ground with some part of his body other than his feet; touch-fall wrestling requires that the opponent be forced into a certain position, usually supine, for a brief instant; pin-fall wrestling requires that the opponent be held in such a position for a measurable length of time; and submission wrestling requires the opponent to vocally or visually signal defeat by his own choice.

Under FILA rules, contests of both international freestyle and Greco-Roman styles of touch-fall wrestling are similar, the object being in each case to throw or press the opponent on his back so that his shoulder blades touch the ground simultaneously. This need occur only for an instant, but a continuous roll across the shoulders is not considered a fall.

The competitors meet on a large padded mat and commence by taking holds from a standing position. Their struggle is observed and controlled by officials, one of whom, the referee, stands on the mat with the wrestlers and signals the award of points for maneuvers leading toward a touch-fall. If no fall occurs before the expiration of the match, these points are used to determine a winner. The actual match is continuous except that it is divided into three periods with a brief rest in between. Ties or draws are common in wrestling.

The competitors make use of techniques that are best learned by practice. While standing, they strive to bring each other to the mat with a series of maneuvers known as takedowns, involving lifting, throwing, twisting, tackling, and tripping. When attacked, a wrestler applies counterattacks to convert the situation to his own advantage. If the wrestlers go down on the mat without a touch-fall, they proceed to grapple, seizing each other with various grips and countergrips to work toward a fall. Great strength, though an asset, is not a prerequisite, since most of the maneuvers employ the principle of leverage; quickness and good physical condition are far more essential. The action in wrestling proceeds at a furious pace and involves all muscles of the body. The use of weight classes prevents the pairing of any two men with more than a few pounds difference between them.